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991.
Small breed dogs (<15 kg) affected by cranial cruciate ligament rupture secondary to cranial cruciate ligament disease are usually middle-aged (mean age at presentation: 5.4 to 9.8 years); terrier breeds, miniature and toy poodles are over-represented. Small breed dogs have a different morphology of the proximal tibia compared to medium and large breed dogs with a steep tibial plateau angle (mean tibial plateau angle 28.8° to 36.3°), absent base of the flare of the tibial tuberosity and a caudally bowed fibula. There is a lack of evidence regarding the optimal management of cranial cruciate ligament rupture in small dogs. The treatment options consist of conservative management, extracapsular stabilisation, cranial closing wedge ostectomy, tibial plateau levelling osteotomy and tibial tuberosity advancement. The limited evidence available shows that conservative management is likely to result in prolonged recovery time (average time to recovery approximately 4 months). There is paucity of reports focussing on extracapsular stabilisation in small breed dogs, and questions have been raised regarding the early failure of the extracapsular suture subject to higher loads due to the steep tibial plateau angle of small breed dogs. Cranial closing wedge ostectomy and tibial plateau levelling osteotomy have been reported to have low major complication rates and good subjective outcomes. It is controversial whether tibial tuberosity advancement is a suitable technique in dogs with steep tibial plateau angle, which includes most small breed dogs. 相似文献
992.
In this study the starch digestion rates in broiler chickens from 18 samples of 5 commonly used feed grains (sorghum, wheat, maize, barley, triticale) were determined. The methodology to determine starch digestion rates in poultry is detailed herein. Starch digestion rates were not significantly different (P = 0.128) across the 18 feed grains, which reflects the wide variations that were observed within a given feedstuff. Nevertheless, starch digestion rates in broiler chickens offered wheat-based diets were significantly more rapid by 56.0% (0.117 versus 0.075 min−1; P = 0.012) than their sorghum-based counterparts on the basis of a pair-wise comparison. In descending order, the following starch digestion rates were observed: wheat (0.117 min−1), barley (0.104 min−1), triticale (0.093 min−1), maize (0.086 min−1), sorghum (0.075 min−1). The implications of these findings are discussed as they almost certainly have implications for poultry nutrition and the development of reduced crude protein diets for broiler chickens. 相似文献
993.
S A Brown G L Coppoc J E Riviere V L Anderson 《American journal of veterinary research》1986,47(4):789-794
Dose-related changes in the pharmacokinetics of gentamicin sulfate were investigated in 9 sheep given 3, 10, or 20 mg/kg of body weight IV in a crossover design with a 24-day washout period. The pharmacokinetics of the 3 mg/kg single dose were compared with that of the terminal phase pharmacokinetics of 3 mg of gentamicin/kg IV every 8 hours for 7 days in 8 additional sheep. Serum concentrations were monitored for 21 to 24 days after the dose. Polyexponential equations were fit to each data set. The number of exponential terms was determined by optimizing the fit for each data set. The pharmacokinetics of the 3 mg/kg single dose were mainly described by triexponential equations. The 10 mg/kg and the 20 mg/kg single doses and the 3 mg/kg multiple-dose data were described by a tetraexponential equation. The elimination rate constant was significantly smaller (P less than 0.05) after the larger single doses, and the serum gentamicin clearance increased as the dose increased (P less than 0.05). The crossover design sequence had a significant effect on serum gentamicin clearance and the area under the curve normalized to unit dose (P less than 0.01). The final exponential phase was not detectable with the present assay sensitivity under the 3 mg/kg single dose. The triexponential equation underpredicted the terminal serum concentrations determined after the 3 mg/kg multiple dose, whereas the 4 phase equation overpredicted the same terminal serum concentrations, perhaps reflecting saturation of the tissue pools that were mirrored by the serum gentamicin concentrations after 24 hours. The present study emphasized the complexity of the terminal phase gentamicin. pharmacokinetics and acknowledged the need for a long-term washout period when using the crossover design for gentamicin pharmacokinetic studies. 相似文献
994.
Unilateral partial arytenoidectomy was performed in 22 horses. Six horses had arytenoid chondritis, 14 horses had idiopathic laryngeal hemiplegia (11 of which had been treated unsuccessfully by insertion of a laryngeal abductor muscle prosthesis), and two horses had laryngeal hemiplegia resulting from perivascular injection of an irritant drug. After surgery, eight horses (36%) developed a nasal discharge of food and/or water that was of clinical significance in only two of them. The operation resulted in marked improvement in exercise tolerance in all 20 horses tested, although two could not work because of severe exercise-associated coughing. Mild inspiratory stertor was present in eight horses and was excessive in one. It was concluded that the high incidence of problems related to swallowing rendered the method unacceptable. Modification of partial arytenoidectomy by silicon augmentation produced improvement in one horse. 相似文献
995.
996.
997.
STUDIES ON EQUINE HERPESVIRUES 总被引:2,自引:0,他引:2
998.
Pathogenesis of placentitis in the goat inoculated with Brucella abortus. II. Ultrastructural studies 总被引:5,自引:0,他引:5
Pregnant goats were inoculated intravenously or in uterine arteries with Brucella abortus, and tissues from the uterus and placenta were examined by electron microscopy. Identification of B. abortus in placentae was with antibody-coated colloidal gold. B. abortus was first seen in phagosomes of erythrophagocytic trophoblasts and in the rough endoplasmic reticulum of chorioallantoic trophoblasts. Subsequently, trophoblast necrosis and ulceration of chorioallantoic membranes were present. Coincidently, B. abortus was present in the lumen of placental capillaries. In late stages of infection, placental vasculitis was present, and placentomal trophoblasts were separated from maternal syncytial epithelium. In lesions with vasculitis, large numbers of B. abortus were in connective tissue of chorionic villi. Within the placentome, trophoblasts that lined chorionic villi contained no intracellular bacteria and were separated from B. abortus by intact basement membranes. These results suggest that bacteremic B. abortus is endocytosed by erythrophagocytic trophoblasts and that B. abortus replicates in the rough endoplasmic reticulum of chorioallantoic trophoblasts. Replication of brucellae in trophoblastic rough endoplasmic reticulum is unique; we believe that B. abortus may utilize endoplasmic reticulum for synthesis and glycosylation of bacterial membrane proteins or that B. abortus catabolizes trophoblast secretory proteins. 相似文献
999.
1000.
J. E. BARNES B.V.Sc. 《Australian veterinary journal》1959,35(7):351-351